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1.
Sensors (Basel) ; 24(5)2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38475191

RESUMEN

The utilization of downhole optical cables has significantly enhanced the efficiency and reliability of oilfield production operations; however, the challenging high-temperature and high-pressure conditions prevalent in oil-gas fields markedly reduce the service lifespan of these optical cables. This limitation severely impedes their application and further development in subterranean environments. In this study, a qualitative analysis was conducted on the structural materials utilized in two types of optical cables to identify these materials and assess the high-temperature tolerance and aging resistance properties of the optical fibers incorporated within. It was discovered that hydrogen infiltration into the subterranean optical cables predominantly accounts for their operational failure. To address this issue, an optical loss testing platform was established, facilitating the execution of a high-temperature and high-pressure hydrogen permeation aging experiment on the optical fibers, allowing for the evaluation of the hydrogen resistance capabilities of the two types of optical fibers. The findings from this study provide a theoretical foundation and methodological guidance for the optimization of optical fibers, aiming to enhance their durability and functional performance in adverse environmental conditions encountered in oil-gas field applications.

2.
Langmuir ; 39(28): 9963-9971, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37390453

RESUMEN

The brittle nature of nanocrystalline metals presents a significant challenge to their widespread application. Extensive efforts have been undertaken to develop materials with high strength and good ductility. In this study, we have discovered a new type of nanocrystalline metal, namely, layer-grained Al, which exhibits both high strength and good ductility owing to its enhanced strain hardening ability as revealed by molecular dynamics simulation. Notably, the layer-grained model displays strain hardening instead of the equiaxed model. The observed strain hardening is attributed to grain boundary deformation, which has previously been associated with strain softening. The simulation findings offer novel insights into the synthesis of nanocrystalline materials possessing high strength and good ductility, thus expanding the potential applications of these materials.

3.
Inorg Chem ; 62(31): 12534-12547, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37490478

RESUMEN

Biomass is a sustainable and renewable resource that can be converted into valuable chemicals, reducing the demand for fossil energy. 5-Hydroxymethylfurfural (HMF), as an important biomass platform molecule, can be converted to high-value-added 2,5-furandicarboxylic acid (FDCA) via a green and renewable electrocatalytic oxidation route under mild reaction conditions, but efficient electrocatalysts are still lacking. Herein, we rationally fabricate a novel self-supported electrocatalyst of core-shell-structured copper hydroxide nanowires@cerium-doped nickel hydroxide nanosheets composite nanowires on a copper mesh (CuH_NWs@Ce:NiH_NSs/Cu) for electrocatalytically oxidizing HMF to FDCA. The integrated configuration of composite nanowires with rich interstitial spaces between them facilitates fast mass/electron transfer, improved conductivity, and complete exposure of active sites. The doping of Ce ions in nickel hydroxide nanosheets (NiH_NSs) and the coupling of copper hydroxide nanowires (CuH_NWs) regulate the electronic structure of the Ni active sites and optimize the adsorption strength of the active sites to the reactant, meanwhile promoting the generation of strong oxidation agents of Ni3+ species, thereby resulting in improved electrocatalytic activity. Consequently, the optimal CuH_NWs@Ce:NiH_NSs/Cu electrocatalyst is able to achieve a HMF conversion of 98.5% with a FDCA yield of 97.9% and a Faradaic efficiency of 98.0% at a low constant potential of 1.45 V versus reversible hydrogen electrode. Meanwhile, no activity attenuation can be found after 15 successive cycling tests. Such electrocatalytic performance suppresses most of the reported Cu-based and Ni-based electrocatalysts. This work highlights the importance of structure and doping engineering strategies for the rational fabrication of high-performance electrocatalysts for biomass upgrading.

4.
Environ Sci Technol ; 57(34): 12732-12740, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37590181

RESUMEN

Nonphotosynthetic microorganisms are typically unable to directly utilize light energy, but light might change the metabolic pathway of these bacteria indirectly by forming intermediates such as reactive oxygen species (ROS). This work investigated the role of light on nitrogen conversion by anaerobic ammonium oxidation (anammox) consortia. The results showed that high intensity light (>20000 lx) caused ca. 50% inhibition of anammox activity, and total ROS reached 167% at 60,000 lx. Surprisingly, 200 lx light was found to induce unexpected promotion of the nitrogen conversion rate, and ultraviolet light (<420 nm) was identified as the main contributor. Metagenomic and metatranscriptomic analyses revealed that the gene encoding cytochrome c peroxidase was highly expressed only under 200 lx light. 15N isotope tracing, gene abundance quantification, and external H2O2 addition experiments showed that photoinduced trace H2O2 triggered cytochrome c peroxidase expression to take up electrons from extracellular nonfermentative organics to synthesize NADH and ATP, thereby expediting nitrogen dissimulation of anammox consortia. External supplying reduced humic acid into a low-intensity light exposure system would result in a maximal 1.7-fold increase in the nitrogen conversion rate. These interesting findings may provide insight into the niche differentiation and widespread nature of anammox bacteria in natural ecotopes.


Asunto(s)
Oxidación Anaeróbica del Amoníaco , Citocromo-c Peroxidasa , Electrones , Peróxido de Hidrógeno , Especies Reactivas de Oxígeno , Nitrógeno
5.
Network ; 34(4): 392-407, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37855276

RESUMEN

The interpeak latency is a crucial characteristic of upper limb somatosensory evoked potentials (USEPs). However, the existing research on the correlation between interpeak latency and consciousness disorders is currently limited. We aimed to investigate how USEPs can contribute to the diagnosis of consciousness disorders. A retrospective analysis was conducted on 10 patients who underwent repetitive transcranial magnetic stimulation (rTMS) for consciousness disorders. The interpeak latency N13-N20, Glasgow coma scale (GCS), and Chinese Nanjing persistent vegetative state scale (CNPVSS) were evaluated before and after rTMS treatment, and the linear correlation between N13-N20, GCS, and CNPVSS was analysed. The scores of CNPVSS and GCS significantly increased in the first, second, and third months after rTMS. The N13-N20 was shorter in the second and third months after rTMS compared to before treatment. rTMS was found to shorten the N13-N20 latency, and there was a negative correlation between N13-N20 and the score of consciousness disorders. N13-N20 can serve as an objective index for evaluating consciousness disorders. This research provides potential insights for doctors in diagnosing patients with consciousness disorders.


Asunto(s)
Trastornos de la Conciencia , Estado de Conciencia , Humanos , Estudios Retrospectivos , Trastornos de la Conciencia/diagnóstico , Potenciales Evocados Somatosensoriales/fisiología
6.
Int Braz J Urol ; 49(6): 740-748, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37903008

RESUMEN

PURPOSE: Considerable controversy exists regarding the surgery for concealed penis. We describe a new technique for repairing concealed penis by symmetrical pterygoid flap surgery. METHODS: From January 2016 to July 2022, we evaluated 181 cases of concealed penis that were surgically treated using the symmetrical pterygoid flap surgery. We measured the penile size preoperative and 2, 4, 12 weeks, and 1 year postoperative to confirm the improvement. A questionnaire was administered to the patients and parents to assess satisfaction regarding penile size, morphology, and hygiene. RESULT: The perpendicular penile length was1.59±0.32cm preoperative and 3.82±1.02 cm after the procedure (p < 0.05), and 4.21±1.91cm after one year of postoperative (p < 0.05). The overall satisfaction of patients was 97.89%, while the overall satisfaction of older children patients (age>7) was 75.24%. Parents focus more on the penile exposure size, while patients focus more on the penile morphology. Almost every patient had postoperative penile foreskin edema. However, this symptom had spontaneously resolved by 4-6 weeks. The complications such as skin necrosis, tissue contracture, or wound infection were 4.42%. CONCLUSION: The symmetrical pterygoid flap surgery is an effective surgical technique for the management of concealed penis in children producing predictable results and excellent satisfaction of the parents and patients.


Asunto(s)
Enfermedades del Pene , Procedimientos de Cirugía Plástica , Niño , Masculino , Humanos , Adolescente , Procedimientos Quirúrgicos Urológicos Masculinos/métodos , Colgajos Quirúrgicos , Pene/cirugía , Prepucio/cirugía , Enfermedades del Pene/cirugía
7.
Biophys J ; 121(23): 4666-4678, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36271623

RESUMEN

Double-layered channels of sinusoid lumen and Disse space separated by fenestrated liver sinusoidal endothelial cells (LSECs) endow the unique mechanical environment of the liver sinusoid network, which further guarantees its biological function. It is also known that this mechanical environment changes dramatically under liver fibrosis and cirrhosis, including the reduced plasma penetration and metabolite exchange between the two flow channels and the reduced Disse space deformability. The squeezing of leukocytes through narrow sinusoid lumen also affects the mechanical environment of liver sinusoid. To date, the detailed flow-field profile of liver sinusoid is still far from clear due to experimental limitations. It also remains elusive whether and how the varied physical properties of the pathological liver sinusoid regulate the fluid flow characteristics. Here a numerical model based on the immersed boundary method was established, and the effects of Disse space and leukocyte elasticities, endothelium permeability, and sinusoidal stenosis degree on fluid flow as well as leukocyte trafficking were specified upon a mimic liver sinusoid structure. Results showed that endothelium permeability dominantly controlled the plasma penetration velocity across the endothelium, whereas leukocyte squeezing promoted local penetration and significantly regulated wall shear stress on hepatocytes, which was strongly related to the Disse space and leukocyte deformability. Permeability and elasticity cooperatively regulated the process of leukocytes trafficking through the liver sinusoid, especially for stiffer leukocytes. This study will offer new insights into deeper understanding of the elaborate mechanical features of liver sinusoid and corresponding biological function.


Asunto(s)
Células Endoteliales , Leucocitos , Hígado
8.
Mol Pain ; 18: 17448069211053255, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35057644

RESUMEN

N-methyl-d-aspartate receptors (NMDARs) dysfunction in the nucleus accumbens (NAc) participates in regulating many neurological and psychiatric disorders such as drug addiction, chronic pain, and depression. NMDARs are heterotetrameric complexes generally composed of two NR1 and two NR2 subunits (NR2A, NR2B, NR2C and NR2D). Much attention has been focused on the role of NR2A and NR2B-containing NMDARs in a variety of neurological disorders; however, the function of NR2C/2D subunits at NAc in chronic pain remains unknown. In this study, spinal nerve ligation (SNL) induced a persistent sensory abnormity and depressive-like behavior. The whole-cell patch clamp recording on medium spiny neurons (MSNs) in the NAc showed that the amplitude of NMDAR-mediated excitatory postsynaptic currents (EPSCs) was significantly increased when membrane potential held at -40 to 0 mV in mice after 14 days of SNL operation. In addition, selective inhibition of NR2C/2D-containing NMDARs with PPDA caused a larger decrease on peak amplitude of NMDAR-EPSCs in SNL than that in sham-operated mice. Appling of selective potentiator of NR2C/2D, CIQ, markedly enhanced the evoked NMDAR-EPSCs in SNL-operated mice, but no change in sham-operated mice. Finally, intra-NAc injection of PPDA significantly attenuated SNL-induced mechanical allodynia and depressive-like behavior. These results for the first time showed that the functional change of NR2C/2D subunits-containing NMDARs in the NAc might contribute to the sensory and affective components in neuropathic pain.


Asunto(s)
Neuralgia , Traumatismos de los Nervios Periféricos , Animales , Depresión/etiología , Humanos , Ratones , Núcleo Accumbens , Traumatismos de los Nervios Periféricos/complicaciones , Receptores de N-Metil-D-Aspartato/metabolismo
9.
Biochem Biophys Res Commun ; 601: 101-108, 2022 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-35240496

RESUMEN

A shielded geomagnetic field, also called the hypomagnetic field (HMF), interferes with the metabolic processes of various cells and animals exhibiting diverse effects in different models, however, its underlying mechanism remains largely unknown. In this study, we assessed the effect on the energy metabolism of SH-SY5Y cells in HMF and found that HMF-induced cell proliferation depends on glucose supply. HMF promoted SH-SY5Y cell proliferation by increasing glucose consumption rate via up-regulating anaerobic glycolysis in the cells. Increased activity of LDH, a key member of glycolysis, was possibly a direct response to HMF-induced cell proliferation. Thus, we unveiled a novel subcellular mechanism underlying the HMF-induced cellular response: the up-regulation of anaerobic glycolysis and repression of oxidative stress shifted cellular metabolism more towards the Warburg effect commonly observed in cancer metabolism. We suggest that cellular metabolic profiles of various cell types may determine HMF-induced cellular effects, and a magnetic field can be applied as a non-invasive regulator of cell metabolism.


Asunto(s)
Glucosa , Neuroblastoma , Anaerobiosis , Animales , Línea Celular Tumoral , Glucólisis , Humanos , Campos Magnéticos , Neuroblastoma/metabolismo
10.
Small ; 18(23): e2201200, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35532198

RESUMEN

Electrochemical nitrogen reduction powered by renewable electricity is a promising strategy to produce ammonia. However, the lack of efficient yet cheap electrocatalysts remains the biggest challenge. Herein, hybrid Cu2 O-CeO2 -C nanorods are prepared on copper mesh through a metal-organic framework template route. The Cu-loaded Ce-MOF is thermally converted to Cu2 O-CeO2 heterojunctions with interfacial Cu-[OX ]-Ce structures embedded in carbon. Theoretical calculations reveal the lower formation energy of oxygen vacancies in Cu-[OX ]-Ce structures than in the Cu2 O or CeO2 phase. The Cu-[OX ]-Ce structures with oxygen vacancies enable the formation of interfacial electron-rich Cu(I) species which show significantly enhanced performance toward electrocatalytic nitrogen reduction with an NH3 yield of 6.37 × 10-3  µg s-1 cm-2 and a Faradaic efficiency of 18.21% in 0.10 m KOH at -0.3 V versus reversible hydrogen electrode. This work highlights the importance of modulation of charge distribution of Cu-based electrocatalysts to boost the activity toward nitrogen reduction.

11.
J Med Virol ; 94(11): 5492-5506, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35879101

RESUMEN

During the long coevolution of human cytomegalovirus (HCMV) and humans, the host has formed a defense system of multiple layers to eradicate the invader, and the virus has developed various strategies to evade host surveillance programs. The intrinsic immunity primarily orchestrated by promyelocytic leukemia (PML) nuclear bodies (PML-NBs) represents the first line of defense against HCMV infection. Here, we demonstrate that microrchidia family CW-type zinc finger 3 (MORC3), a PML-NBs component, is a restriction factor targeting HCMV infection. We show that depletion of MORC3 through knockdown by RNA interference or knockout by CRISPR-Cas9 augmented immediate-early protein 1 (IE1) gene expression and subsequent viral replication, and overexpressing MORC3 inhibited HCMV replication by suppressing IE1 gene expression. To relief the restriction, HCMV induces transient reduction of MORC3 protein level via the ubiquitin-proteasome pathway during the immediate-early to early stage. However, MORC3 transcription is upregulated, and the protein level recovers in the late stages. Further analyses with temporal-controlled MORC3 expression and the major immediate-early promoter (MIEP)-based reporters show that MORC3 suppresses MIEP activity and consequent IE1 expression with the assistance of PML. Taken together, our data reveal that HCMV enforces temporary loss of MORC3 to evade its repression against the initiation of immediate-early gene expression.


Asunto(s)
Infecciones por Citomegalovirus , Proteínas Inmediatas-Precoces , Adenosina Trifosfatasas/metabolismo , Citomegalovirus/genética , Proteínas de Unión al ADN/metabolismo , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Proteína de la Leucemia Promielocítica/genética , Proteína de la Leucemia Promielocítica/metabolismo , Replicación Viral
12.
Sensors (Basel) ; 22(16)2022 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-36015820

RESUMEN

In view of the risk of collision with humans or equipment arising from a lack of protection in the operation process of combined support and anchor equipment on the heading face, this paper designs a safety interlock system for combined support and anchor equipment. Firstly, a mathematical model of hydraulic power system control and a valve control system based on feedforward-feedback optimization were established according to the power demand of the combined support and anchor equipment. Secondly, according to the reliability indexes of the safety interlock system, corresponding sensor, logic control and execution modules were designed. Ultrasonic sensor groups were arranged at the key positions of the combined support and anchor equipment to capture the position information in real time when the equipment was moving. Thus, the pump-valve hydraulic system was controlled through closed-loop feedback. The experimental results show that the safety interlock system of the combined support and anchor equipment can adjust the revolving speed of the permanent magnet synchronous motor (PMSM) in real time according to the distance from the obstacle, so as to control the pump outlet flow, and then perform interlocking safety control of the hydraulic cylinder's movement speed. The system can effectively prevent damage to the surrounding equipment or personnel arising from equipment malfunction.


Asunto(s)
Imanes , Modelos Teóricos , Diseño de Equipo , Retroalimentación , Humanos , Reproducibilidad de los Resultados
13.
Biophys J ; 120(9): 1650-1664, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33684350

RESUMEN

The connector protein, also known as the portal protein, located at the portal vertex in the Phi29 bacteriophage has been found to play a key role in the genome DNA packaging motor. There is a disordered region, composed of 12 sets of 18-residue loops N229-N246, that has been assumed to serve as a "clamp" to retain the DNA within the pressurized capsid when DNA is fully packaged. However, the process remains undefined about how the clamping of DNA occurs and what signal is used to engage the channel loops to clamp the DNA near the end of DNA packaging. In this study, we use the planar lipid bilayer (PLB) membrane technique to study the connector with its loops cleaved. The channel properties are compared with those of the connector with corresponding wild-type loops at different membrane potentials. On the basis of the hypothesis of the Donnan effects in the flashing Brownian ratchet model, we associate the PLB experimental results with the outcomes from the relevant biochemical experiments on the proheads containing the connectors without the loops, which enables us to provide a clear picture about how the DNA clamping occurs. A mathematical relationship between the Donnan potential and the DNA packaging density is established, demonstrating that they are both in essence the same signal that is received and transmitted by the connector to dictate DNA clamping and the termination of DNA packaging. At the end of the study, the PLB technique is proposed as a viral research tool, and its potential use to study the functions of specific domains in a portal protein of the tailed bacteriophages is highlighted.


Asunto(s)
Fagos de Bacillus , Membrana Dobles de Lípidos , Fagos de Bacillus/genética , Cápside , Empaquetamiento del ADN , ADN Viral
14.
Small ; 17(40): e2102413, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34494360

RESUMEN

Molybdenum phosphide (MoP) is regarded as one of the most promising alternatives to noble-metal based electrocatalysts for efficient hydrogen evolution reaction (HER) due to its similar d-band electronic structure to noble metals and tunable features associated with phase and composition. However, it still remains a great challenge to construct MoP electrocatalysts with abundant active sites that possess ideal H binding strength to promote catalytic performance. In this work, it is found that by anchoring a rare earth compound, cerium phosphate (CePO4 ) on MoP (CePO4 /MoP), the stabilized Ce3+ in CePO4 can significantly boost the formation of oxygen vacancies in ceria (CeO2 ) in situ formed on CePO4 surface during HER, which effectively regulates the d-band electronic density-of-states of MoP, increases the numbers of active sites, and promotes the vectorial electron transfer, therefore greatly enhancing the HER performance of MoP. The optimized CePO4 /MoP/carbon cloth (CC) electrocatalyst exhibits a significantly improved HER performance with an overpotential of 48 mV at 10 mA cm-2 and a Tafel slope of 38 mV dec-1 , about two times better than the HER performance of MoP catalyst without CePO4 (with an overpotential >80 mV dec-1 at 10 mA cm-2 ), very close to commercial Pt/C catalyst.


Asunto(s)
Hidrógeno , Molibdeno , Cerio , Electrónica , Fosfatos
15.
Small ; 17(11): e2006617, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33605080

RESUMEN

A robust polyaniline-assisted strategy is developed to construct a self-supported electrode constituting a nitrogen, phosphorus, sulfur tri-doped thin graphitic carbon layer encapsulated sulfur-doped molybdenum phosphide nanosheet array (NPSCL@S-MoP NSs/CC) with accessible nanopores, desirable chemical compositions, and stable composite structure for efficient hydrogen evolution reaction (HER). The multiple electronic coupling effects of S-MoP with N, P, S tri-dopants afford effective regulation on their electrocatalytic performance by endowing abundant accessible active sites, outstanding charge-transfer property, and d-band center downshift with a thermodynamically favorable hydrogen adsorption free energy (ΔGH* ) for efficient hydrogen evolution catalysis. As a result, the NPSCL@S-MoP NSs/CC electrode exhibits overpotentials as low as 65, 114, and 49 mV at a geometric current density of 10 mA cm-2 and small Tafel slopes of 49.5, 69.3, and 53.8 mV dec-1 in 0.5 m H2 SO4 , 1.0 m PBS, and 1.0 m KOH, respectively, which could maintain 50 h of stable performance, almost outperforming all MoP-based catalysts reported so far. This study provides a valuable methodology to produce interacted multi-heteroatomic doped graphitic carbon-transition metal phosphide electrocatalysts with superior HER performance in a wide pH range.

16.
J Org Chem ; 86(23): 16396-16408, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34781678

RESUMEN

A one-pot method for the selective synthesis of two isomers 4H-chromene and 2,8-dioxabicyclo[3.3.1]nonane derivatives was developed without a catalyst and using EtOH/H2O (4:1, v/v) as the solvent. The reaction was conducted under mild conditions, with forming multiple chemical bonds in one pot and high atom economy, and only a stoichiometric amount of H2O is produced as the byproduct. Its selectivity was controlled by thermodynamics and kinetics, and the reasons for the transformation of the two structures are also discussed.

17.
Environ Sci Technol ; 55(24): 16627-16635, 2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34889591

RESUMEN

Antibiotics are widely found in nitrogen-containing wastewater, which may affect the operation stability of anaerobic ammonium oxidation (anammox)-based biological treatment systems. Extracellular polymeric substances (EPSs) of anammox sludge play a pivotal role in combining with antibiotics; however, the exact role and how the structure of the leading component of EPSs (i.e., extracellular proteins) changes under antibiotic stress remain to be elucidated. Here, the interaction between sulfamethoxazole and the extracellular proteins of anammox sludge was investigated via multiple spectra and molecular simulation. Results showed that sulfamethoxazole statically quenched the fluorescent components of EPSs, and the quenching constant of the aromatic proteins was the largest, with a value of 1.73 × 104 M-1. The overall binding was an enthalpy-driven process, with ΔH = -75.15 kJ mol-1, ΔS = -0.175 kJ mol-1 K-1, and ΔG = -21.10 kJ mol-1 at 35 °C. The O-P-O and C═O groups responded first under the disturbance of sulfamethoxazole. Excessive sulfamethoxazole (20 mg L-1) would decrease the ratio of α-helix/(ß-sheet + random coil) of extracellular proteins, resulting in a loose structure. Molecular docking and dynamic simulation revealed that extracellular proteins would provide abundant sites to bind with sulfamethoxazole, through hydrogen bond and Pi-Akyl hydrophobic interaction forces. Once sulfamethoxazole penetrates into the cell surface and combines with the transmembrane ammonium transport domain, it may inhibit the NH4+ transport. Our findings enhance the understanding on the interaction of extracellular proteins and sulfamethoxazole, which may be valuable for deciphering the response property of anammox sludge under the antibiotic stress.


Asunto(s)
Compuestos de Amonio , Aguas del Alcantarillado , Oxidación Anaeróbica del Amoníaco , Anaerobiosis , Reactores Biológicos , Simulación del Acoplamiento Molecular , Nitrógeno , Oxidación-Reducción , Sulfametoxazol
18.
FASEB J ; 33(2): 3051-3062, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30351993

RESUMEN

Recent studies suggest that peroxiredoxin1/2 (Prx1/2) may be involved in the pathophysiology of postischemic inflammatory responses in the brain. In this study, we assessed the distribution and function of Prx1/2 in mice after experimental subarachnoid hemorrhage (SAH). We investigated the distribution of Prx1/2 in the brains of mice both in vivo and in vitro using immunofluorescence staining. The expression of Prx1/2 after SAH was determined by Western blot. Adenanthin was used to inhibit Prx1/2 function, and Prx1/2 overexpression was achieved by injecting adeno-associated virus. Oxidative stress and neuronal apoptosis were assessed both in vivo and in vitro. The neurologic function, inflammatory response, and related cellular signals were analyzed. The results showed that Prx1 was mainly expressed in astrocytes, and Prx2 was abundant in neurons. The expression of Prx1/2 was elevated after SAH, and their expression levels peaked before proinflammatory cytokines. Inhibiting Prx1/2 promoted neuronal apoptosis by increasing the hydrogen peroxide (H2O2) levels via the apoptosis signal-regulating kinase 1/p38 pathway. By contrast, overexpression of Prx1/2 attenuated oxidative stress and neuronal apoptosis after SAH. Thus, early expression of Prx1/2 may protect the brain from oxidative damage after SAH and may provide a novel target for treating SAH.-Lu, Y., Zhang, X.-S., Zhou, X.-M., Gao, Y.-Y., Chen, C.-L., Liu, J.-P., Ye, Z.-N., Zhang, Z.-H., Wu, L.-Y., Li, W., Hang, C.-H. Peroxiredoxin 1/2 protects brain against H2O2-induced apoptosis after subarachnoid hemorrhage.


Asunto(s)
Apoptosis/efectos de los fármacos , Lesiones Encefálicas/prevención & control , Encéfalo/fisiología , Proteínas de Homeodominio/metabolismo , Peróxido de Hidrógeno/farmacología , Sustancias Protectoras/farmacología , Hemorragia Subaracnoidea/fisiopatología , Animales , Encéfalo/efectos de los fármacos , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Corteza Cerebral , Proteínas de Homeodominio/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Oxidantes/farmacología , Estrés Oxidativo , Transducción de Señal
19.
Exp Mol Pathol ; 115: 104469, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32445751

RESUMEN

OBJECTIVE: To uncover the expression patterns of HOXB2 and FOXC1 in Wilms tumor samples, and their synergistical regulations on the development of Wilms tumor. METHODS: Expression levels of HOXB2 and FOXC1 in 58 cases of Wilms tumor tissues and paracancerous ones were detected. The influences of HOXB2 and FOXC1 on prognosis in Wilms tumor patients were analyzed. Their regulatory effects on proliferative and migratory abilities in WT-CLS1 and HFWT cells were examined by cell counting kit-8 (CCK-8) and Transwell assay, respectively. The interaction between HOXB2 and FOXC1, and their synergistical regulation on the development of Wilms tumor were finally explored. RESULTS: HOXB2 and FOXC1 were upregulated in Wilms tumor tissues. Higher levels of HOXB2 and FOXC1 indicated higher risks of advanced stage and lymphatic metastasis, as well as worse prognosis in Wilms tumor patients. Knockdown of HOXB2 or FOXC1 weakened proliferative and migratory abilities in WT-CLS1 and HFWT cells, while the opposite trends were observed in those overexpressing HOXB2 or FOXC1. The positive interaction between HOXB2 and FOXC1 was identified, which synergistically drove the malignant development of Wilms tumor. CONCLUSIONS: HOXB2 and FOXC1 are upregulated in Wilms tumor samples, and they are closely linked to tumor staging and lymphatic metastasis in Wilms tumor patients. HOXB2 and FOXC1 synergistically drive the malignant development of Wilms tumor by stimulating proliferative and migratory potentials.


Asunto(s)
Progresión de la Enfermedad , Factores de Transcripción Forkhead/metabolismo , Proteínas de Homeodominio/metabolismo , Factores de Transcripción/metabolismo , Tumor de Wilms/patología , Regiones no Traducidas 3'/genética , Adulto , Secuencia de Bases , Línea Celular , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Masculino , Unión Proteica , Adulto Joven
20.
Chemistry ; 25(9): 2330-2336, 2019 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-30549117

RESUMEN

As one of the most efficient systems for photocatalytic hydrogen evolution, the Z-Scheme system, consisting of different semiconductors with a reversible donor-acceptor pair, has attracted great attention. Considering the non-toxicity and low cost of photocatalysts, a series of g-C3 N4 /α-Fe2 O3 hybrids were rationally constructed based on the Z-Scheme mechanism for the first time, using a metal-organic framework template approach that can fine tune the compositions and properties of the hybrids. An optimized hybrid, g-C3 N4 /α-Fe2 O3 -2, exhibited prominent photocatalytic water splitting performance with a visible light response. Under irradiation of visible light (λ>420 nm), the hybrid shows a high durability and superior hydrogen production rate of 2066.2 µmol g-1 h-1 from water splitting, which is approximately three times greater than that of bulk g-C3 N4 because of the effective separation of photo-excited charge carriers by two narrow band gap semiconductors, tightly coupled with the Z-Scheme structural feature.

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